net: phy: fix phy_validate_pause

We have valid scenarios where ETHTOOL_LINK_MODE_Pause_BIT doesn't
need to be supported. Therefore extend the first check to check
for rx_pause being set.

See also phy_set_asym_pause:
rx=0 and tx=1: advertise asym pause only
rx=0 and tx=0: stop advertising both pause modes

The fixed commit isn't wrong, it's just the one that introduced the
linkmode bitmaps.

Fixes: 3c1bcc86 ("net: ethernet: Convert phydev advertize and supported from u32 to link mode")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>